Research On Power Allocation Based On Game Theory In Simultaneous Inforamtion And Powe Transfer System

As wireless communication technology plays an important role in modern economy,the access of a large number of mobile devices and the explosive growth of wireless service demand in the telecommunication industry make the wireless spectrum resources more scarce.Therefore,the contradiction between the demand for high data transmission rate and the scarce spectrum resources becomes increasingly tense.At the same time,with the rapid growth of power consumption in the telecommunications industry,the energy consumption of wireless devices has become an urgent problem.As a very promising solution,wireless power transfer(WPT)can solve the limited energy problem of wireless mobile devices,and it is satisfy the concept of green communication.Therefore,aiming at solving the problem of energy limitation and spectrum resource shortage,it has great value to study a reasonable and effective resource allocation scheme in the wireless power transmission network,which can improve the system data transmission and solve the charging problem of mobile devices.Based on the above research background,to solve the problem of limited energy and improve the transmission rate,we studiy the power allocation problem in wireless communication system considering WPT.In the process of establishing system model,we combine the traditional wireless communication network with multiple-input multiple-output(MIMO)technology,full-duplex(FD)technology and wireless relay technology to improve the transmission rate of the system.For different network architectures,we jointly design and optimize the transmit power and beamforming by using game theory and alternative optimization theory.The main research contents include the following aspects.An FD relay system model based on simultaneous wireless information and power transfer(SWIPT)is proposed,which realizes the simultaneous transmission of information and energy by configuring a power splitting receiver at each terminal.Combining FD relay communication mode with SWIPT technology,we formulate a optimization problem,which takes the system transmission rate as the objective function,the relay transmit power and the collect power at the power splitting(PS)receiver as the constraints.As the variables in our established problem are coupled,we propose an alternative optimization scheme to optimize the transmit power and penalty factor,respectively.Considering the competition in the proposed system model,we formulate the original problem as a non-cooperative game problem,and solve the Nash equilibrium using Karush-Kuhn-Tucker(KKT)conditions.Then,we propose an iterative alternating optimization algorithm based on KKT conditions and fixed step projection method,and prove the convergence of the algorithm by the definition of Nash equilibrium and diagonal strict concave condition.Simulation results show that the transmission rate of our proposed algorithm is better than the non-iterative scheme,half-duplex(HD)relay scheme,self-interference partial elimination scheme and the scheme without penalty,which verifies the effectiveness of our proposed algorithm.An FD relay MIMO system model based on SWIPT is proposed,which can improve system transmission rate and the network coverage efficiently.An optimization problem is established,which takes the system transmission rate as the objective function,the total transmit power of transmitters,the relay transmit power and the collect power at the PS receiver as the constraints.As the variables in the optimization problem are coupled and difficult to solve,an iterative optimization scheme based on alternative optimization theory is proposed,which can decouple the original problem by optimizing the transmit power and beamforming.In the proposed power allocation problem,the competitive optimization problem is established as a non-cooperative game problem,and the Nash equilibrium is solved by water-filling method.Considering the complexity of MIMO relay beamforming,the original problem is modeled as an equivalent mean square error(MSE)problem.Then,we convert the matrix optimization problem into a scalar optimization problem based on singular value decomposition(SVD),which reduce the complexity of algorithm.According to above analysis,an iterative algorithm based on game theory and SVD is proposed to jointly optimize the transmit power and beamforming,which is proved to be convergen.Simulation results show that the transmission rate of our proposed algorithm is better than the non-iterative scheme considering the constraints of transmit power and collect power.The system transmission rate increases with the increase of the number of antennas,and our proposed algorithm can converge to Nash equilibrium quickly.Considering the interference channel,a multi-relay MIMO system is proposed to study the interference minimization and power allocation problem,which can improve the system transmission rate efficiently.An optimization problem is established,which takes the system transmission rate as the objective function,and takes the total transmit power of transmitters,the transmit power of the relay and the collected power of the terminal as constraints.An interference minimization scheme is proposed based on SVD to minimize the interference introduced by multi-relay,which can reduce the complexity of our proposed algorithm.Considering the coupling of multiple "transmitter-relay-terminal" communication links,the original problem is modeled as a non-cooperative game problem,which convert the centralized problem to a distributed problem,and the Nash equilibrium is solved by KKT conditions.To improve the system transmission rate,an iterative alternative optimizing algorithm based on game theory and fixed step projection method under the condition of interference minimization is proposed,which can minimize the interference of system and allocate the transmit power reasonably.Finally,the efficiency of the algorithm is verified by simulating the transmission rate of different power allocation schemes,and the convergence is verified by simulating the relationship between the transmit power and the number of iterations.Simulation results show that the transmission rate of our proposed algorithm is better than the non-iterative scheme,the HD relay scheme and the scheme without penalty optimized.The system transmission rate increases with the increase of the number of antennas.